


The Second Set of Experiments

by hellogaywatson



Category: Marvel Cinematic Universe, The Avengers (Marvel Movies)
Genre: Bruce is Hulk and Hulk is Bruce, Consent is Sexy, M/M, Pepperony - Freeform, Polyamory, Pre-Established Relationship, Science Bros, Still Extremis! Pepper, for science, nonverbal Hulk
Language: English
Status: In-Progress
Published: 2017-07-10
Updated: 2017-07-23
Packaged: 2018-11-30 14:00:06
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 4
Words: 13,047
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11465049
Author URL: https://archiveofourown.org/users/hellogaywatson/pseuds/hellogaywatson
Summary: After what they discovered during that week back in spring, it was probably inevitable that this would follow.





	1. Ask a Question

**Author's Note:**

> This is my submission for [Science Bros Week 2017](http://sciencebrosweek.tumblr.com/), which goes from July 10-16 with a prompt for each day of the week:  
> Monday - Light  
> Tuesday - Pending  
> Wednesday - Rush  
> Thursday - Pierce  
> Friday - Triumph  
> Saturday - Eclipse  
> Sunday - Yours
> 
> I am also posting on my [Marvel tumblr](https://pepperonywsciencehalf.tumblr.com/), updating by day or whenever I get the prompts done. :D
> 
> This story follows directly after [One Week in Spring, 2013](http://archiveofourown.org/works/7706884/chapters/17561707), but you don't need to read it for this to make sense.

He’s got his head in the middle of a calculation when Bruce shoves him.

“Shove” is perhaps an unfair description for Bruce poking him in the shoulder with his index finger, but at this size a mere poke from Bruce is something akin to manhandling. It’s enough force for Tony to actually lose his balance while sitting down, only because his brain was devoted to more important things than keeping his body upright, and the bulk of his torso thunks against Bruce’s kneecap.

“What,” he says, “you bored already?  It’s been like ten minutes, give me a break.”

He looks back to his tablet and tries to pick up where he left off, but Bruce pokes him again, purposefully harder, and keeps pushing with one finger until Tony’s back flat against the floor.  He looks up and up at Bruce, giving him the performative scrunched-up perturbation face he saves for the people he really likes.

“You’re crouching in on my territory.  I’m supposed to be the annoying one here.”

He grabs onto Bruce’s finger and feigns pulling it off of him – he’ll never be strong enough to actually do it – and Bruce plays along, letting Tony go free so he can sit up again lotus style across from Bruce, who is seated the same way but with infinitely more green majesty.  Tony’s head only comes up to the middle of his torso, the spot where his pectorals finally stop and a set of abdominal muscles of mythological proportions begins. He hasn’t quite gotten used to seeing him just sitting there all huge and ripped and chill – that body looks like one destined for perpetual motion, and to be fair even his breathing is still kind of a seismic event.

It was a matter of careful days over weeks before they’d managed to get this far.  They’d started slow with Bruce fully briefed, knowing exactly where he was and what was going to happen before he made the change.  In this way they’d managed to get a large sample of blood with the help of the talented Dr. Cho, and they’d done some basic experimentation to test the effectiveness of the confinement chamber and then to see just how strong Bruce could really get.  It was all very clinical, and they’d never intended for it to be anything more than that.

But hey, best laid plans and all that.  They’d learned more than they bargained for.  That there was a lot less space between tiny pink science Bruce and supersized green smashing Bruce, for one.  And for another, that a willful transformation under low-stress conditions was kind of like scratching the ultimate itch.

Hence days like today, when Bruce shifts just for the decompressive hell of it and they, y’know, hang out.

They still use The Cage, because the vibranium-lined confinement chamber is the biggest open space in the Tower that isn’t also full of extremely expensive delicate equipment. But now that they’ve chilled down here enough times for Tony to stop worrying that Bruce will run like a scared rabbit and plow through seven layers of wall, he doesn’t always shut the door behind him.

Heart and mind aside, there’s still some major differences between little Bruce and big Bruce.  Big Bruce, for example, has none of the patience with important research and development that little Bruce does.  Or patience with much of anything at all, for that matter.  Thus the shove-poking.

Tony won’t necessarily admit that he kind of loves it.  He’s come to think of the Hulk as no-filter-Bruce.  Tiny bro will never straight up say, “Hey, pay attention to me.” Large bro has no qualms about it whatsoever.  He likes that Bruce has at least one state of being where he’ll demand things.

He also likes that there’s a state of being where he can climb Bruce like a tree, which after a few moments of the two of them sitting and dopily beaming at each other is exactly what he proceeds to do.

There’s a constant chicken-egg loop he goes through where he’s not sure if he was waiting his entire life to have a friend big enough to count as a landscape, or if it’s awesome because any and all Bruce-related stuff is awesome.  Do I love you because I have possibly developed a size kink, or have I developed a size kink because I love you?

Like all chicken-egg loops the answer doesn’t matter all that much in the face of the here and now where he can hug Bruce’s neck the way he would hug most people around the waist. He doesn’t think of himself as a small person – short, sure, often and painfully, but not small.  He’s bulked out in the muscle sense and the chubbiness sense, and he’s used to being wrapped up in enough metal to dent concrete. It’s a new experience to feel light as dandelion fluff, like a strong gust of wind might blow him away, but that’s very much the illusion he gets when he can hang off of Bruce as a human cape.

In spite of all his work with the pull-up bar it takes a helping hand for him to make it all the way up to Bruce’s shoulder.  It’s not so big that he doesn’t have to watch his balance, and the uppermost part of Bruce’s clavicle digs into his ass a little bit, but it’s worth it for the novelty of being able to perch there.

He’s always trying to figure out the math, if Bruce is one and a half or twice his size or something in between, but it honestly kind of depends which bit because the proportions are a little off.  Like his hands are huge even compared to the rest of him, and the sheer bulk of muscle makes his head look a little too small.  Tony will probably get curious enough eventually to come in with a couple of yardsticks and a long measuring tape, get some real data and see if he can find the golden ratio anywhere for shits and giggles.  As it is he’s been measuring Bruce in more intimate ways. He knows, for example, that his own hand is just big enough to wrap around Bruce’s thumb, and that if Bruce spreads his fingers he can span Tony from armpits to waist.

He runs his hands idly through Bruce’s hair, digging in with his fingernails a little to get him to make that deep, rumbling purring sound he loves so much.  That hair feels so soft and, well, _fresh_ is a weird word to use but he can’t think of a better one. He wonders for the thousandth time if the transformation is a complete and total cellular regeneration or if it builds on what’s already there, takes the matter that makes up Bruce and amplifies it.  And, inexplicably, colors it in.  They’re on the edge of figuring it out, he’s certain of it.  Bruce has been examining the samples in earnest since they started sharing space like this (which can’t be entirely coincidence), and the things he ponders out loud as he peers through a microscope at himself are getting more cohesive by the day.

Whatever the case, Hulk hair feels like it was just recently snatched out of the nearest molecules. All of him feels like that, fresh and new.  On his daring days Tony jokes that they could market that, having baby-soft hands that can rip a car in half, and on Bruce’s upbeat days it makes him laugh.

Bruce gets a bit more catlike, nuzzling at Tony with his face, and sure it’s cute but it’s also precarious – one over-enthusiastic _klunk_ and Tony’s heading rapidly floorward.  Luckily Bruce’s reflexes at this size are also catlike, and he catches Tony with one hand before supporting him with both.  Another measurement – a single hand is enough space for him to sit as long as he doesn’t mind the barstool effect of a cheek occasionally sliding off; both hands become a luxury recliner.

He likes this a lot, when Bruce holds him in two hands and together they take the shape of an old-school monster movie poster but with significantly more chill.  He likes to be able to see Bruce’s face, to see a smile that big on it, and to watch the color of his eyes shift as the different parts of his psyche ebb and flow.  It always feels corny afterwards and he doesn’t know how to ask for it.  He thinks he should be better at asking for things by now, but he’s so afraid that he’ll say the wrong thing and scare Bruce away from…

From what, what’s the word for it?  Being himself?  This is all so conceptually difficult still if he really thinks about it, and he _has_ to think about it, to make an effort, because when he leans against Bruce and feels him breathe and listens to that bass drop of a heartbeat it all seems so deceptively simple.

Bruce’s breathing makes him more conscious of his own, the expansion of ribs shoving gently against his body, and he slows his inhales, takes the oxygen in deeper, until they match. Tony presses two fingers to the left side of his own chest and sure enough, even their heartbeats are starting to sync, and it’s funny that this is the only way they can, that Bruce has to get this big for his heart to beat slow and steady instead of thrumming like an overgrown hummingbird.

He could fall asleep like this, it’s so damn peaceful, and maybe he already is a little bit, slipping in and out of dreams.  There’s datasets scrolling in front of his eyelids, the numbers from his work a few minutes earlier, and he shoos them away as if they were a pesky insect. Nothing that can’t wait until later. Only Bruce math for now.  Best kind of math.  Breath-to-heartbeat ratio.  Inhale-two-three-four-five-six, hold-two, exhale-two-three-four-five…

“Hey,” he says sluggishly, numbers ticking in his chest, a memory of sunlight and expansive green skin tangling up on the edge of his brain with the current suffusion of warm Bruce-smell.  “Can I kiss you?”  He shoves gently against Bruce’s chest in an effort to indicate desired motion.  “On the mouth, I mean.”

Bruce answers by lifting him up just so, and Tony beams him a fond, sleepy smile before cupping his chin and leaning forward to peck, distinctly reminded of hot coffee mug pressed to his lips early in the morning – _one, two._

Hulk’s mouth is two Tony-kisses wide, if he rounds up from 1.6 or thereabouts, which he does because it’s impossible to administer .6 of a kiss.  Kiss-fractions are not useful units of measurement.

He watches the brown bleed across Bruce’s irises, watches him do the nervous little tongue-flick which he’s never seen before at this size – it’s ridiculously endearing, and for a second it’s all he can do not to imagine Bruce in an extra-large pair of thin-rimmed reading glasses.  Although getting bigger and greener apparently cures farsightedness, at least in this particular case.  Bruce gusts a warm sigh over his face and hums gently enough that Tony can only just feel it vibrating in his sternum, and a single finger curls up to nudge his lower back, urging him forward.

“Ok,” he says, “I don’t know if I’m reading you right here, with you not being the most verbose guy and all, but to me that seems to indicate ‘what the hell are you stopping for,’ was I close?  Ok, ok,” he chuckles as Bruce nudges harder, “I get it,” and he lets his weight fall forward.

He doesn’t peck this time, parts his lips and presses Bruce between them, alternating from top to bottom and back again, and it’s only when he first dips his tongue carefully into the wet heat of Bruce’s mouth that he realizes, _hey, I asked for something._

Mathematical curiosity makes asking for things easier, apparently.

He runs his tongue along the inside of Bruce’s bottom lip, swipes it over his teeth, and oh _wow_ , he can feel Bruce’s pulse speeding up where his thigh is pressed against Bruce’s wrist, _that’s_ an interesting sensation, especially given the way his pants are getting a little tight.  This is probably the right time to stop and think, to reflect on the situation, but to hell with it, warm and soft and Bruce smells _so good_ and he feels greedy with joy that he gets to do this, that he’s the first and only person to date who’s ever gotten Hulk-make-outs.

He works an arm around Bruce’s head, dragging blunt nails across his scalp, and he can’t help the noise he makes when Bruce gives him his tongue, just the very tip through Tony’s parted lips, enough that he can brush his own tongue against it before sucking hard, and Bruce makes a startled sound of his own, almost an _oh –_ all in a rush Tony is set down, hard enough that it jars his legs.

Sometimes the transformation is so fast that he swears he can hear the _whoosh_ , the air rushing in to fill the space like a roll of thunder.

He pushes himself to his feet, rising to meet a smaller, shakier Bruce who cups Tony’s face in his hands, begging with his eyes for something neither of them could put a name to, his breath coming hard with a mixture of excitement and paralytic fear.


	2. Do Background Research

Tony buys a custom mattress.

 

“I don’t know how to talk about this,” Bruce admits against the shell of his ear, curled up around him. They’re in Bruce’s bed between muted jade green sheets, the color different enough from his bigger skin that it doesn’t seem like a joke.  Bruce likes green even when he doesn’t like himself, likes the quiet determination of chlorophyll.  His living room is a jungle of healthy houseplants.

They’re in his bed because it’s his, somewhere entirely familiar and comfortable where his control is almost more than an illusion.  Tony wants him to have all the comfort he can today, and every other day too, if he really thinks about it.  “I don’t know either.”

“But I’m going to try.” Bruce lets out a long exhale and slides his hand over Tony’s hip.  They’re both dressed in pajama pants and t-shirts, eliminating at least the distraction of each other’s skin.

“There was a time,” Bruce says, “when I thought I was going to have to content myself with no more than handshakes and the occasional hug for the rest of my life.  Like I truly, honestly thought that.  First, back when I still thought transformation was intrinsically linked to heart rate.  And then when I figured, it would go one of two ways.  Either people wouldn’t want me because of – what I can do, or they _would_ want me because of it.  And that seemed almost worse.”

His hand squeezes, fingers pressing hard against the crest of Tony’s hipbone, and he gives a shaky sigh. “I never _dreamed…_ ”

It was only a few months ago that Tony never dared turn around when he heard the tremor in Bruce’s voice, that he’d continue to face the wall and pretend for both of their sakes, and he’s so, so grateful that now he can roll over and let Bruce press his face into his chest, right over the spot where his skin tone shifts ever so slightly under his shirt.  He wishes he could feel more of it.

“What is it you see?” Bruce asks.  “When we’re down there.  How does that – what do you see?”

That’s a sneak attack, really, although he’s sure Bruce doesn’t mean any malice by it, but it’s really about two dozen questions disguised as one, so Tony gives a sneaky answer back.

“…you.  I see you.”  He kisses the top of Bruce’s head.  “You’re just a complex guy, is all.”

Bruce responds with a quiet shudder of laughter, curling his fingers into the fabric of Tony’s shirt.

“I don’t ever have to do that again,” Tony tells him.  “Not that, not – not anything else like it, if you don’t want me to.”

“Oh, Tony.”  Bruce’s fingers clench even tighter, enough that he can feel fingernails through the cotton.  “I want you to.  I want you to so much it terrifies me.”

 

Tony buys a custom mattress and it’s harder to find a seller than he thought it would be, but also much less expensive than he expected, so he really splurges on the sheets.

 

“I don’t know how to talk to you about this,” he admits to Pepper, apropos of nothing.

On the bright side, the look she gives him over the edge of her book implies that she’s anticipating hearing about something along the lines of him burning down her apartment, so there’s nowhere to go but up.

“I think you have a right to know, but not in the same sense as usual, I mean, if I start sleeping with someone new I want to tell you but I’m not sure this qualifies as someone new and it’s not like there’s an impact on STI risk what with the total immunity-”

“Tony,” she says, setting the book in her lap still open spine-up with a bemused smile, “is this you asking for my blessing to start having Hulk sex?”

“…I’m not sure if ‘blessing’ is the concept I was going for, I guess I was just looking to be forthright and also get some kind of reaction, which I admit I thought would be…more…”

“Freaked out?”

“Well, yeah.”

“This time last year, I might have been.”  She swings her legs down off the couch and pats the empty space with her hand, and he sits.

“You are you,” she explains, “and you love Bruce Banner, and I would have been infinitely more shocked if you told me you’d never thought about being intimate with him when he’s…” Tony quirks an eyebrow at her. “…bigger,” she finishes, with an eyebrow raise of her own.  “In fact I’m surprised it took you this long.  Also grateful, because if I hadn’t – _seen_ him like that, gotten to know him like that, I would’ve been much more worried.  But we had a good talk.”

“You talked with Bruce?”

She lifts her hand up above her head to indicate height.  “Big Bruce.”

“Wait – when did this happen?  How did I not know about this?”

“What, can’t a girl have a decent conversation with her metamour once in a while?”  

He has a sudden mental image of Pepper in one of her perfect suits shaking hands with buck-naked Hulk as if they’re sealing a business transaction, all red and green like Christmas, and can’t keep the giggle from escaping his nose.  “I’m sure that was a stimulating conversation, considering how you can’t shut him up.”

Pepper fake-punches his arm.  “No, it was good!  …it was good. It helped with all the-”  She waves her hand limply in front of her and looks down at her lap.  “-post-December shit.”

“Oh.”  For all his more recent self-awareness he still hates the times when he actively feels like an asshole.

“Don’t get emotional on me,” she demands with another light punch.  “The point is that you’ll only be going up to having two lovers who could conceivably rip your arms out of your sockets, so it’s not like I have any stones to throw.”

He grimaces.  “Well, that’s a sobering mental image.”

Pepper wraps her arm around his shoulders and gives him a squeeze.  “We all of us here have pretty uniquely fucked-up lives.  May as well grab on to the good parts.”

“Anyway,” she adds as an afterthought, picking her book back up, “I don’t trust _you_ not to do anything outrageously stupid.  But I trust _Bruce._ ”

 

The box barely fits in the service elevator.  There’s a distinct squeak of cardboard and tape against wall as they finally manage to get it all the way in.  Tony tries and fails not to think of it as some kind of weird metaphor.

It’s unwieldy as hell but somehow they manage to get it into the Cage without breaking anything, Bruce effortlessly supporting one end, Tony straining and having a few near-death experiences on the other.  Neither one of them was brave enough to ask for help from the delivery guy.

Once they get all the cardboard and plastic off they find it curled up like a sushi roll.  Bruce carefully reads the manual and Tony not-so-carefully cuts the restraints and they both step rapidly out of the way as the thing starts to take on air.

“Well,” Bruce says once the hissing has stopped and roughly a third of the floor of the Cage is covered in mattress.  “That was fucking magical.”

 

“Why is it that you don’t talk?” Tony asks much later.  Bruce takes a moment to consider and Tony holds still to let him, which he thinks takes a commendable amount of discipline on his part.

“Everything’s just so _big,_ ” Bruce finally replies, and laughs breathlessly alongside Tony’s snort before explaining, “no, no, I mean _everything_ , everything on the inside too.  All of his – all of my senses are so intense, everything’s brighter and louder and smellier – Tony, _fuck_ – and-and everything _feels_ so – so strong, I mean you’ve seen what that looks like, the anger, the fear, but the good things too, it’s all just so big and overwhelming that he just – I don’t think about talking, and anyway there doesn’t seem to be anything to _saahhhh-_ ”  Bruce breaks off as Tony curls his fingers; he wants to hear what Bruce has to say but wants just as much to turn him incoherent.

“So-so with that as it is,” Bruce gasps, “if we’re doing _this_ , I’ll probably talk even less.”

“I don’t know that we’ll be doing this, specifically,” Tony points out, curling and pressing again for the perfect little sound he gets, for the clench around his fingers.  “I don’t think this would do much for you, at that scale.  For you to _really_ feel it like that,” he adds, lower and darker, “I’d have to use my whole _hand_ ,” and Bruce immediately rewards him with a groan, loud and utterly unapologetic.  “Maybe we can work our way up.”

“Come on,” Bruce growls, and this time the clenching is absolutely intentional, entirely under his control. “Jesus, Tony, come _on-_ ”

“So demanding,” Tony murmurs, slipping his fingers out and reaching for the condom.  He and Bruce had come easily to the agreement that before any further experimentation they needed to work out a nonverbal system of basic communication, and that such a system should be tested in the most high-intensity environment possible outside of actual transformation.  Fortunately for them both, Bruce’s highest level of intensity in this body is having his knees pushed to his ears.

He hitches Bruce’s legs up over his shoulders and lines himself up, taking a moment to admire how that looks, all the curves and angles, as he nudges Bruce’s entrance.

“Please,” Bruce whimpers, and Tony can tell from his tone that he’s crossed into that beautiful headspace where he’s completely past embarrassment.  “Tony, _please._ ”

“Ssshhhh.”  He presses a finger to Bruce’s lips and Bruce immediately darts out his tongue to lick a wet stripe up the length of it, making Tony’s cock twitch against his ass.  “No more talking.”

He sinks in inch by careful inch, watching Bruce’s head fly back, his eyes flutter shut, his teeth nibble into the plush of his lip, and waits until he bottoms out to start asking questions.  “Are you ok?”

Bruce lifts a trembling right hand and taps Tony’s left shoulder, softly, with one finger.   _Yes._

“How is that?”

Another single tap – _good_ – and then he opens his eyes, holding Tony’s gaze, and presses his finger to his arm again, this time dragging the tip down to the elbow.

Somehow Tony understands, but he checks first, just to be sure.  “Deeper?”

_Yes._

He adjusts the pillow under Bruce’s ass and rolls him back, folding Bruce in half, huffing a breath as he feels himself sink further, and Bruce cries out, starts tapping furiously – _yesyesyesyesyesyes –_ a drumroll of enthusiastic consent against Tony’s skin.

Tony was thinking about the practicalities going in, was thinking about keeping it simple and unmistakable, so much so that he never realized how fucking _hot_ it would be.  Now that he’s got Bruce underneath him giving him a crash course in this new language – the tap of _yes_ and the quick drag of _more_ and the long squeeze of _there_ and the sudden, startling bite of fingernails into skin that can’t be anything but an obscenity – _now_ it’s all sinking in, this amalgamation of glorious present and future potential, and although Bruce isn’t speaking, exactly, he’s by no means quiet either.  It makes self-control an incredibly demanding feat, and it’s never easy anyway when they’re doing this, keeping his pace slow and steady, pushing gently into Bruce right where he needs, resisting the temptation to speed up and chase his own climax.

It’s never easy but it’s always worth it.

Bruce stutters into silence, muscles in his thighs twitching against Tony’s body, and Tony has that signal down pat, holds himself deep as Bruce starts to keen, pushing against Tony’s left arm with all of his strength as he soaks Tony’s belly and himself and a remarkable amount of the bedspread.  Tony waits until the convulsions around him stop before he speeds up, briefly giving over control and slamming into Bruce until he feels a light tap on his right arm.

_No._

“Sorry,” he pants, stilling immediately, “shit, I’m sorry, too hard?  Oversensitive?”

There’s a _yes_ and one of the strokes that he’s been taking for _more_ , which in this case obviously means _keep going but not so hard, ok?_

He carefully lowers his torso down, propping himself up on his arms, which makes this into a kind of intense core exercise but at least this way he can kiss Bruce’s mouth.  He works him slowly with his tongue, thrusting deep but gentle to a few sleepy _yeses_ until the pressure and the warmth start pooling in the pit of his belly and he stretches into his own orgasm.

Bruce wraps his arms around him as he pulses, pressing warm palms to his back, then releases him so he can gently withdraw and roll off.  He takes in deep, shaky breaths and rolls his head to the side to watch Bruce glow, which he’ll be doing for at least the next ten minutes.  Bruce always shines especially bright after he’s been good and fucked.

“Amazing as that was,” he says once he’s finally able to pry his attention away from Bruce and look at his arm, “it might be a little dangerous at a bigger size, if these marks are any indication.”

Bruce turns and frowns thoughtfully at the collection of bruises and scratches.  “I think it would be in your best interest not to lead with prostate stimulation.”

“Like I said,” Tony says, raising his arm up and smiling fondly at his battle scars, “we can work our way up.”


	3. Construct a Hypothesis

“This is ungodly comfortable,” Bruce says, arms and legs stretched wide.  “I may never sleep in my own bed again.  I may just move in down here.  This is my home now.”

“Told you I didn’t scrimp on the bedding.”  Tony beams down at Bruce from his position above him, hands propping him up on either side of the other man’s head.  “Just imagine how good it’s gonna feel when you’re naked.”

“Which begs the question of why I’m _not_ naked.”

“’Cause I wanted to take your clothes off myself,” Tony explains, nuzzling his neck, “instead of watching you put them in that clinical little pile on the table like always.”

“Mm.”  Bruce smiles and tips his head back further, offering more neck for the application of Tony’s lips and teeth.  “Ok.  I can get behind that.”

Bruce’s clothes are extra good today; he’s got this short-sleeved light blue button-down made of the kind of cotton that feels slightly rough to the touch and he’s wearing _jeans_ which Tony swears he only does bi-monthly, and he doesn’t understand at all because jeans are clearly the Superior Type of Pants and why would you _not_ wear them all the time if you had the chance?  But Bruce treats them the way some people treat dress pants, so this is a rare and incredibly sexy occurrence worthy of celebration, and Tony can’t think of a better way than getting them off of Bruce as fast as possible.

“Jarvis,” he murmurs as he flicks the first button open, “mood lighting, please.”

The bright unforgiving white of the LEDs overhead shifts slowly into a more muted and gentle blue-white. Bruce takes in a sharp breath.  “Haven’t seen _that_ shade in a while.”

“Mmm.”  Tony continues down the row of buttons, kissing as he goes. “I thought you might like it.”

“Classical conditioning is a remarkable thing,” Bruce comments breathily, rising up on his elbows a little as Tony pushes his shirt off his shoulders and runs a hand though the hair on his chest.  “I’m pretty sure seeing that color of light would instantly get me hard, assuming, y’know, that I wasn’t already.”

“I would never assume.” Tony noses at the hair surrounding Bruce’s navel and then kisses, feels muscle jump under his lips. “Maybe next time I should get some candles going down here.”

“Hm, yeah, Hulk and candles, what could possibly go wrong?”

“Don’t worry, I’m sure this mattress is coated in industry standard anti-flammable neurotoxins.” Bruce half-laughs half-moans as Tony bites down against his hip.  “Really, though, I’m regretting my lack of foresight.  I could’ve had champagne, rose petals, the whole shebang.  Too much is not enough for an occasion as prestigious as your pseudo-deflowering.”

Bruce wrinkles his nose. “Virginity is such a waffly concept anyway, I think ‘pseudo’ is about the best anyone can do.  That being said, with the right application of context and imagination you could deflower me as many times as you want.”  Tony groans thoughtfully and puts a big bright pin in _that_ for later.  “Now,” Bruce continues, flashing him a grin just the right side of feral, “get these pants off of me before I wreck them.”

Which Tony is more than glad to do, tossing the jeans along with the shirt out of any potential damage radius before applying his mouth directly to the bulge in Bruce’s dark grey boxer briefs.

“Prediction,” he pulls away to say once Bruce’s hips settle back down against the mattress.  “You’ll sustain this-” and here he squeezes the head of Bruce’s cock, making him twitch “- through transformation.”

“Counter-prediction,” Bruce pants, still grinning.  “You won’t know what to do with it once you’ve got it.”

Tony makes a sound of mock indignation and mercilessly tickles Bruce under the arms.  Bruce shrieks and tries to defend himself, forcibly removing Tony’s hands from his armpits, at which Tony goes for the knees instead and almost gets a kick in the face for his trouble.  They spend the next few minutes like that, locked in low stakes combat, and Tony suspects that Bruce knows as well as he does they’re both extra goofy today because they are just the tiniest bit afraid.

“Prediction,” Tony says once they’ve calmed down, lifting Bruce’s hips so he can slide the boxer briefs off and toss them the way of the pants and shirt.  “If everything is bigger, as you so eloquently put it, then orgasm is going to be fucking spectacular.”

Bruce suddenly gets very quiet and still.  His breathing, excited and erratic only moments before, evens out, as if he’s purposefully trying to slow it, to regain control.  The mood in the room plummets like it’s been shot out of the sky and Tony wishes like hell he could turn back the last thirty seconds and unsay it.

“I don’t know if that’s going to work,” Bruce says softly with an empty smile.  “An experience that overwhelming even at this size, where I give up that level of control, could be…dangerous.  Intense joy, an anger rampage, it’s all the same if I could hurt you and not even realize it until it’s too late.  So…”  He gives a short laugh.  “It’s probably not possible.  I’m…I’m sorry.”

“No.  Bruce…no.”  Tony shakes his head slowly.  “That’s ok. It’s ok.”  He drags his thumb across Bruce’s cheek, as if he can wipe the apology away like a teardrop.  “You – you know it’s ok, right?”

Bruce takes both of Tony’s forearms in his hands.  “Come here and kiss me.”

Tony does, lets his body drape over Bruce like a blanket as he kisses him gentle and deep, trying to say with the motion of his tongue and his lips all the affirmations he knows Bruce doesn’t want to hear spoken in words.  Bruce kisses back, humming contentment, and Tony feels him swell up and get fully hard again against the inside of his denim-clad thigh.

“We can still test that initial prediction of yours,” Bruce murmurs against his lips, closing his eyes for a moment, and when he opens them again they’re bright green, tinted with a hint of blue by the light.

“Shit,” Tony responds eloquently.  “Oh holy shit.  Holy fucking _shit-_ ”

He knows the feel of Bruce shrinking under him, the slide of skin as he compacts and Tony’s body suddenly covers all of him instead of only a third of him, but this, _this-_

This is new.

He winds up centered directly on Bruce’s chest, lifted up slightly with each breath, and once the shock and awe have worn off enough he immediately looks behind him.

“Well how about that,” he breathes.  “Tony Stark was right again.”

Bruce snorts and turns Tony’s face back toward him with a single big finger, pushing down against his back with another, but Tony holds out a hand – “Ah-ah-ah-ah-ah, nope, wait. Hold up.  Trial run.”  Bruce takes his hands off of him, hovering them to either side of him, and Tony holds his eyes with his best serious face.

“Tell me no.”

The touch is so gentle it takes his breath away a little, coming to grace his upper right arm before trailing away.

“…tell me yes.”

This touch is less gentle and remains there on his arm, dragging slowly down, pressing firmly enough that his body tilts to the side.  Before Bruce’s finger reaches his elbow he says, “Can I kiss you?” and Jesus, his breathing’s already shot to hell.

 _Yes,_ Bruce replies, harder than the first time, and Tony descends, digging his hands into Bruce’s hair and tugging himself up to crush his mouth to Bruce’s lips, nuzzling and sucking until he’s sure every trace of melancholy is gone, eradicating any sadness that stretched and grew alongside skin, muscle, and bone.   _This is enough._ He shouts the words inside his head as if he can get them inside Bruce via osmosis, like he can slip them into Bruce with his tongue.   _Any of this would be enough.  You are enough.  My cup runneth over.  You are more than enough, you are a whole universe._

This time when he sucks Bruce’s tongue, Bruce doesn’t get smaller – he _purrs_ , a warm steady rumble that Tony can feel in every bone in his body, and Bruce’s fingers steal under the hem of his t-shirt to press heat against his belly and back.

“Oh,” he says, all his muscles tensing, releasing.  “Oh,” and he gets on his knees and lifts his arms up to let Bruce carefully, so carefully, tug his shirt up and over his head.

He’s never had these hands against his bare skin before.  It’s almost like he’s still clothed, like he’s wearing Bruce now instead of his shirt, flushing from his face to his navel.  Bruce’s pinky digs under the waistband of his pants, pressing against the cleft of his ass, and when Tony laughs it sounds utterly broken, just wrecked.  “You – you better let me do that.”

He unbuttons his fly and slides the zipper, hooking his thumbs under his underwear and inching everything down, good and showy the way Bruce has always liked, and Bruce flashes him a bright-eyed grin, familiar except that it’s got maybe a few more teeth than usual now.  Tony has to sit back a little ungracefully to get his pants all the way off, but Bruce holds patiently still until he chucks them off into the corner and gets on his knees again, sitting back against his heels on Bruce’s chest.

He’s sweating more and faster than usual with all the warmth of Bruce underneath him, and he can tell Bruce is sweating too because of the smell, the one he usually has to chase by pressing his face right to Bruce’s groin, now salty and pervasive all around him. It shoots straight from his nose to his cock and he moans, twitching, already aching just from the heat and the scent, and then Bruce’s finger traces soft, soft, along his underside from root to tip, and the noise he makes is so loud that it actually embarrasses him a little.

“Can I-”  His breath is so ragged that it’s hard to get the words out.  “Can I kiss you all over?”

_Yes._

“Do you like it when I use my teeth?”

_Yessssss._

“Do you have any fucking _idea_ how hot you are?”

Bruce doesn’t merit that with an answer, just rumbles gentle laughter as Tony falls forward and kisses his mouth again, and he’s never heard, never _felt_ a laugh so big.

He scrapes his teeth over Bruce’s throat, tugs at the thick, black hair on his chest, rakes his nails across one of his nipples, all the things he knows Bruce likes when he’s small except that he can do them so much _harder_ like this, kind of has to in order for Bruce to feel them at all, in fact. Bruce is helpfully responsive, making deeper, darker versions of the sounds Tony is used to, and while Tony’s left arm is still free of bruising it’s getting one hell of a workout.

Tony makes a grand tour of Bruce’s torso, kissing and biting until finally, finally he’s close enough to reach down and drag his hand through the dark triangle of course hair, so close, almost touching – “Can I – can I-”

_No._

He immediately snatches his hand away, but Bruce keeps tapping, gentle but forlornly insistent – _no, no…no…_  Tony takes the short journey back up to the top of his chest to meet his eyes, and they’re so very full, too full, of sorrowful guilt.

“Big guy.  Hey.  Hey.” He sinks his hands back into Bruce’s hair, rubs the base of his skull while he makes soothing, hushing sounds, kisses his chin, his cheek, his brow.  “It’s ok.  It’s ok. I want you to tell me no when you need to.  Ok? That’s _good_.  That’s why we talk.  It’s ok.” Bruce makes a sad keening sound, and Tony rubs a little harder.  “Can you promise me you’ll always do that when you need to?  Will you tell me no when I do something you don’t want?”

… _yes._

“Good.  That’s good.  You’re so good, Bruce.”  He kisses Bruce’s mouth, a single light touch of lips this time.  Bruce puts a fingertip to his chest, pressing gently enough that he understands he’s not being pushed away, and he traces a circle, over and over, as if he’s drawing the pattern of where the arc reactor used to be.

“What would you like me to do?  You want me to keep kissing you?”

_Yes.  Yes._

He smiles against Bruce’s skin, and this time he draws it out, spending a good five minutes on Bruce’s neck alone with lips and tongue and teeth until Bruce is breathing deep and shaky, trembling slightly under Tony’s body.

Tony slides down until his mouth is at Bruce’s collarbone, nibbling along the edge of one clavicle, then the other, before dipping his tongue into the hollow in the middle.  Bruce gasps and bites back some kind of sound, loud enough that Tony hears his teeth clack, and his hips rock involuntarily, pressing the length of him against Bruce’s pectoral so that he has to bite against a groan of his own.  He looks up quickly to gauge Bruce’s comfort, but his eyes are closed as he breathes heavily through parted lips.

Tony moves down a little farther, tracing the edge of Bruce’s pec with his fingers, feeling the firmness of the muscle there, and whistles under his breath.  Bruce’s chuckle is somewhat strained, and Tony gets the feeling that he’s focusing hard on sustaining form, that he’s actively trying not to change back, putting the transformation off as long as he can. Tony does something he’s always wanted to try on this body, knowing that he may be running out of time, and sucks Bruce’s nipple into his mouth.

He’s still sensitive, if the full-body jerk is any indication.  Tony smiles and sucks harder, running his tongue over the ridges of skin, stroking Bruce’s chest hair.  He’s big enough to be a literal mouthful, and Tony realizes that the increase in size gives him better control, that he can swipe his tongue along the bottom curve and shape his lips to the top, as opposed to covering the entire thing with the tip of his tongue.  He nips once to test the give of the skin and then bites down hard.

Bruce moans, his hips jerking, jostling Tony as he licks and then bites again, greedy for Bruce to keep making that sound, his own hips rocking rhythmically, and before he can stop and check if all of this is ok Bruce’s hands come up and hold him in place, exerting just enough pressure than he can feel the squeeze in his shoulders and chest.

He cries out and strains backward against Bruce’s hands, bucks forward against his belly, his cock rubbing against Bruce’s abdominal muscles, feeling them tense and relax, leaving a wet trail that glistens in the dim light.  Tony takes in a deep, shaky breath, filling his lungs with Bruce’s smell until everything in his head twists and melts away leaving only heat and salt and the sweet, throbbing ache between his legs, and he ruts.

Every stroke of his hips burns him, smooth sensitive flesh sliding over hot ridges of muscle, and the pleasure runs so deep it’s like his body is learning all over again.  Bruce’s hands hold him steady, squeezing tighter in the most minute of increments as he gets closer and closer to the edge, and he can feel Bruce’s index finger moving on his left arm, coaxing, stroking, turning his brain inside out as if it were Bruce’s voice in his ear – _that’s it, good, good, you’re so good, Tony, so good for me, let me see you, I want to see you fall apart for me –_

He crashes his head against Bruce’s chest and _roars_ , clenching up all over as the tidal wave of pleasure rushes up his spine and taps his brain, exploding into light behind his eyes, and he pulses over and over against Bruce’s belly, shaking and almost sobbing but not so overwhelmed that he doesn’t feel Bruce’s skin sliding and shifting underneath him.

“Tony.   _Tony_.”

He opens his eyes, chest still heaving, and looks up at Bruce’s face, sees the sadness there, the empty ache of longing, and shakes his head as if that might somehow make it go away.

“Tony,” Bruce whispers, “I wish…I wish I could…”

And somehow he understands.

“Ssh.”  He pulls Bruce against him, clenches up with one last shiver, and sighs.  “It’s ok. It’s ok.  You can now.”  

It’s not entirely true, because even now Bruce will be holding back, always too strong, always too powerful, but it strikes Tony that it’s the fate of all the lovers that ever were, every single human being, to have the power to hurt the people they cherish most.  Every hug, every kiss, every fuck is a matter of carefully applied strength.

“Let go,” he tells Bruce, smoothing his hands up and down his back.  “Let go.  Lose your everloving shit on me, big guy.”

Bruce laughs softly against his neck, then sinks his teeth in without warning, biting down hard enough to leave a mark as his hips start to move.


	4. Test with an Experiment

Tony can’t help but notice that this was apparently the tipping point Bruce needed, that now he’s finally starting to strut on an almost full-time basis.

Bruce is consistently happier, and he’s showing it with his whole body.  He fidgets less.  He talks louder.  He lets himself take up more space on the couch, in the lab, in the universe at large. He’s started to laugh, really genuinely laugh, in front of people who are not Tony, including people he barely knows. He’s getting more comfortable with Pepper, adopting the same open posture and easy way of speaking with her that he has with Tony, and a few times Tony’s even walked into one of their communal living spaces to find the two of them talking animatedly like old friends.

Best of all (at least in Tony’s ever-so-humble opinion), Bruce is getting better at casually initiating touch, throwing an arm around him in front of the entire floor-double-eight R&D team, kissing him goodbye the days he has to leave for the office, cuddling up next to him on the couch and not immediately sitting up ramrod-straight and putting space between them if Pepper or Happy or Rhodey comes into the room.  He’s starting to treat touching Tony as a nice, everyday thing instead of limiting it to behind-closed-doors desperation.  Although there’s still plenty of that too, thank god, and once a week or so when Bruce has him backed against the nearest convenient surface and they’ve been kissing and fondling long enough to get all hot and bothered, Bruce will put his lips to Tony’s ear and whisper, “You want to take this to the Cage?”

If someone had told Tony back in early spring that by May he’d be getting turned on at the mere _mention_ of the Cage, he would have scoffed.

Bruce is also getting more comfortable with being big, which of course was one of Tony’s not-so-ulterior motives for Hulk intimacy in the first place.  He’s better able to relax when they’re making out, rumbling contentment instead of struggling to hold form, getting carefully but more persistently handsy.  One time he even stays big after Tony’s gotten off, letting his body be used as a heated mattress as Tony comes down from his orgasm-high.

So Tony’s getting a bit more daring too, hence his experiment today of testing whether Hulk is ticklish.

His efforts are yielding two potential answers: 1) apparently not; 2) yes but nothing Tony can do with his own puny body is effective and in order to get a tickle-reaction he’d have to do something like shoot Bruce at point-blank range with some kind of projectile, which just _no_. His memories of the way Bruce roared when faced with the laser-fire of a Chitauri squadron are still plenty vivid, thanks.

It’s a blessing that Bruce’s Hulk-skin is still sensitive if not as ticklish, so when Tony kisses his belly and hips he gets the shivers and sighs even if he’s missing out on the giggle fits.  Bruce has one hand floating gently over Tony’s back, hovering so light that he can just feel the heat of it and the light press of the meaty part of Bruce’s palm. He’s entirely focused on the warmth above and below him and the way the hairs around Bruce’s navel tickle his face, so it’s absolutely unintentional when he backs his ass up directly into Bruce’s erection.

“Oh geez,” he mutters as Bruce lets out a confused little whine – little in that it doesn’t shake the walls of the Cage.  “Sorry sorry sorry oh O _K_ then,” as Bruce grabs his hips with sudden ferocity and grinds him back against his dick.

Tony was sort of hoping the first time he touched Bruce’s cock post-transformation it would be with his hands, but hey, he’s adaptable.  He cants his hips back a bit to get more friction and the sensation suggests all kinds of physical impossibilities but it feels pretty good for all that, hot and hard against the curve of his ass and the sensitive skin between his legs.

It’s good for Bruce too if his noises are any indication, breathy moans that vibrate through Tony’s body as Bruce pushes him back over and over and over again.  His hips start to rock, bucking forward to meet each of Tony’s presses back, and Tony’s getting dizzy, moaning himself at the way it all feels, Bruce’s hands and his cock and his _need._  The thought that lube would improve this experience for both of them drifts vaguely through his head, and he’s about to make the suggestion when Bruce’s hands grip hard enough to knock the wind out of him, crushing against his ribs until he has to gasp, “Too tight, too tight, too _tight-_ ”

Bruce lets him go instantly and Tony takes a deep gulp of air into his poor abused lungs as Bruce shrinks, crying out as he goes, giving a truly impressive sample of his full vocal range.  “Sorry,” he pants once he regains his speech faculties, “Tony, I’m sorry, please, I just, I needed to be _smaller-_ ”

Tony’s all ready to go with a barrage of soothing sounds and comforts as well as a fair number of suggestions for how to go longer and farther next time, if that’s what Bruce wants – he doesn’t expect Bruce to pin him down against the mattress and grind on him, breathing hot and desperate into his ear –

“God, Tony, I wanna fuck you so _bad_ , wanna get inside of you, please, please, Tony _please-_ ”

“Nnngah,” Tony manages, trying to ground himself and think in spite of the whirlwind of Bruce’s arousal going on directly on top of him.  

Bruce’s filter tends to only kick back in post-transformation after he’s had a good long nap, this is not news.  But what Bruce is talking about now has been the ultimate taboo between them even moreso than Hulk-based intimacy, and hearing him not only bring it up but _beg_ for it while they’re both naked and sweaty and Bruce’s erection is pressing up insistently against Tony’s own aching cock is…just…a lot.

They could do it, too, Tony knows they could.  It would be easy with this nice soft bed, with all the lube, like a _lot_ of lube, that Tony’s had down here since they moved the mattress because it’s always better to be prepared.  He’s even got a pack of condoms in one of the desk drawers out in the lab in case there was ever a day Bruce didn’t want to wait until they’d gotten all the way back upstairs to get fucked, and god Bruce is _not_ helping, whispering a litany of pleading and promises accentuated by each roll of his hips –

“Please, Tony, I think about it all the time, how you’d feel, how you’d _sound_ , I wanna push inside you and feel you warm and tight around me, all around me, wanna make you feel good like you do for me, make you feel _so_ good, want it _so bad-_ ”

“The lord is testing me,” Tony sighs on a single miserable exhale, and he wraps his arms around Bruce’s back and rubs his hands slowly up and down, up and down.  “Sssshhh, Bruce.  Sssshhhh. I hear you.  I hear you.  But we’re gonna talk about it later, ok?  We’re gonna talk about it but we’re gonna wait until…’til you’ve calmed down a little bit.  All right?” Bruce’s babble quiets and turns into a gentle whimper.  “Theeeeeere we go.  We’ll talk. I promise.  Just…not like this, ok?  There we go.  C’mere. I got you.”  He brings a hand up to his mouth, smears it good and wet with spit, and wraps it around Bruce’s cock.  “I got you.”

Bruce makes a choked sound as if he’s been wounded and pushes forward, and Tony keeps one hand on his back, rubbing soothing patterns as Bruce fucks the tight ring of his fist. After a few minutes Bruce tenses with a broken moan and spends himself in Tony’s hand, letting Tony hold him close as he trembles and remembers how to breathe.  Tony carefully lets go and wipes his hand on the sheets, then watches Bruce’s eyelids grow heavy with the combined exhaustion of post-transformation and post-orgasm until they close completely and his breath comes deep and even.

Tony lies prone next to his sleeping lover, sighing with a combination of relief and frustration.  It’s like every fantasy he’s ever tried not to have about Bruce fucking him is attacking him at the same time, a full year’s worth of suppressed yearning assaulting his brain and body until his ass feels as flush with blood as his dick, everything from his tailbone to his pelvis one giant, throbbing ache.  He rolls to his side and covers his mouth with one hand to muffle his groan as he takes his cock in the other and pointedly fails to not think about Bruce pushing inside of him, stretching him out, filling him with hard, slick heat and it’s hardly any time at all before he’s coming over his fingers.

Bruce’s hand comes to rest soft on his back, creeping up over his shoulder, and he takes the fingers in his hand and squeezes, letting Bruce pull him into a somewhat feeble embrace before the welcome emptiness of sleep takes him over.

 

They wake up, and they don’t talk about it.

Bruce dresses with a stiff smile and talks about a lot of other things, his work with R&D, the reading he’s done over the week, their weekend plans.  They clean up in their separate living spaces and go to work on their separate floors in their separate departments, and Tony has some prospective suppliers to wine and dine over the dinner hour, and in between when they see each other they don’t talk about it so hard that it hurts.

But it hurts Tony far, far more to see Bruce beginning to collapse back in on himself, like he’s trying to trigger another kind of transformation and shrink down even smaller than he already is.

After dinner (which he admittedly rushed a bit, but not so much that he doesn’t have some great opportunities ahead for cost-effective arc miniaturization), he rockets up to Bruce’s apartment without even bothering to take of his tie and jacket and raps on the door.

Bruce answers looking decidedly world-weary.  He’s wearing khakis and a checkered shirt, feet bare, hair fluffy, still with his glasses on so he must have been reading, and for a second Tony wants nothing more than to take him in his arms and hug him tight.

“We’re talking now,” he says instead, and Bruce actually tries to _shut the door_ , like not hard but he’s swinging it shut and Tony feels fully justified sticking his leg out dramatically so that it knocks against his kneecap instead.

“Talking,” he says again, somewhat pained, and Bruce scrunches up his face and heaves a heavy sigh through his nose but he turns around and heads for the sofa without any further attempts to thwart Tony’s entrance.

Tony takes a moment to remove his shoes and hang his jacket over one of the chairs in the breakfast nook before winding his way through the sea of green life and joining Bruce on the sofa.  He keeps his posture relaxed, one arm thrown over the back, one foot resting on the opposite knee, to counteract the tension of Bruce sitting curled up on the far end white-knuckling an accent pillow.

“So,” he tries to begin, but Bruce immediately cuts him off –

“Could we just pretend that this morning never happened?”

“We could,” Tony says slowly.  “That’s a viable option.”

Bruce is still wearing his glasses, purposefully making the world blurry, absolving himself from seeing Tony’s facial features with any kind of clarity.  “I think,” Tony continues, “that we’d have to pretend pretty hard.”

Bruce wraps the pillow in his arms, hugging it to his chest, staring straight out in front of him. His throat is doing the fluttery thing that happens when he’s uncomfortable.  Tony tried to replicate it in the mirror once but he couldn’t figure out which muscles to activate.

“You know,” Tony says, “I’ve had a lot of sex over the course of my life.”

“Yes,” Bruce responds flatly, “I do know that.”

“I mean, a _lot_ of sex.”

“That’s what they tell me.”

“I threw my back out during sex once.  And this was still in my thirties, mind you.  Incredibly embarrassing.  I couldn’t move normally for weeks.”  He lowers his leg off his knee so he can put both feet on the floor and angle himself towards Bruce.  “I have been squeezed too tight and bitten too hard.  I have used inadequate amounts of bad-quality lube.  I have not had safewords when I really, _really_ should have had safewords.”

“Your point,” Bruce says without shifting his gaze.

“My point.  Right.”  Tony looks down at his stocking feet, wiggles his toes a little.  “Uh – no idea, honestly.  I didn’t prepare some big speech, I don’t know what to say at all, only know that I need to say something.”

Bruce lets a mirthless laugh out against the pillow.  “Well, thanks for being honest-”

“You want to fuck me.”

“ _Christ,_ Tony.”  Bruce looks up at the ceiling with another loud huff of breath.

“What, you don’t want to, you were bullshitting me this morning or what?”

“You can’t – you can’t make _decisions_ based on things I say when I’m like that.  You have to treat it like, I don’t know, like I was drunk. Completely shit-faced.  You know?”

“I do know, which is why we’re talking about it like two very sober adults right now, and which is _also_ why I didn’t let you do to me this morning what you so obviously wanted to do after having clammed up at the mere mention of it for well over a year.  I don’t do that, I don’t take advantage, Bruce, and I don’t do coercion either, that’s not what this conversation is for, so if at any point it feels like that’s where it’s going to you, you’re in your full rights to shut me up and show me the door.”

Bruce finally makes eye contact which is a relief even if he does look as if a pair of headlights are bearing down on him.  Tony gives him a tight-lipped smile.

“But,” he continues.  “People when drunk have a tendency to tell the truth.  To be over-generous with it, in fact.  I’m trying to figure out what to do with this new information, now that I know that in your darkest heart of hearts or whatever there’s something you really want to do that I would really, _really_ like you to do, and since we both want it so much maybe we should take a thorough look at our reasons for, well, not doing it.”

“Tony, you _know_ why.”

“Because you could transform in the middle and break my ass with your enormous green dick?”

Bruce makes a noise of utter misery and buries his face in the pillow.

“Oh, big guy.”  Tony scoots closer and puts a cautious hand on Bruce’s back, keeps it there when he doesn’t flinch away.  “Excuse my bluntness.  But that _is_ why, right?”

“Sometimes,” Bruce says, a bit muffled, “I think I would _kill_ to be normal.”

“Ok, well, now you’ve driven me to insert the obligatory comment about how if you were quote-unquote normal we never would have met.” Tony is also not sure that Bruce would’ve survived being normal.  He thinks that Bruce might not be anywhere on earth at all if he hadn’t had a big green rage monster beating inside of his heart to keep him alive.  But that’s something he’ll never say out loud no matter how drunk he gets.

Bruce gets his head out of the pillow and gifts Tony with something that’s at least related to a smile, maybe a second or third cousin. “What a cheap shot.”

“I have never even once claimed to be above cheap shots.” He runs his hand up and down Bruce’s back, turning the rubbing into methodical scratching when there are no objections.  “At the risk of sounding like a besotten sap, I would _so_ much rather have a Bruce whose dick is admittedly big enough at times to do major bodily harm than no Bruce at all.”  Bruce groans at that, but he chuckles a little bit through it.  “I would be perfectly happy never to get fucked by you if that was what you wanted.  But it’s not, apparently.  Why _is_ that?”

Bruce furrows a single incredulous eyebrow.  “Are you honestly asking me _why_ I want to fuck you?  Really?  That’s…an unusually grand display of humility.”

“I mean sure, who wouldn’t, etcetera etcetera, but I’m asking it as a serious question.  Truly.”

Bruce raises a hand to his forehead and drags his fingers through his hair.  “Well, I know how much you’d like it, for all you claim not to care.”

“Yeah, knowing me like you do I guess it’s no great secret how much I like it up the ass.”  He smirks at Bruce’s snort of laughter, tapping a finger to his lips.  “But is that where all the appeal is, in how much I’d enjoy it?  ‘Cause that’s a concerning amount of selflessness motivation-wise.”

“No, it’s…not all altruism,” Bruce confesses, shaking his head. He sets the pillow on the floor and sits in thoughtful silence for a few seconds, then removes his glasses, folding them and placing them on the low table in front of the sofa.  

“Tony,” he says, “I want everything with you,” and Tony is struck by how different it is having Bruce’s eyes meet his when there’s no lenses in the way; it makes a lump come up in his throat that wasn’t there before. “If I could, if I _could_ …I wouldn’t even think about reserve, I’d hold you and kiss you and fuck you and never hold anything back.  And _god_ , Tony, I wish I could, that I could let go of all the fear and just _feel_ you, every time.  I wish I didn’t have to be so careful.”

Tony sucks on his bottom lip, biting at it inside his mouth where Bruce can’t see, and tries to put a lid on the wave of guilt spreading from the pit of his stomach all across his chest, making everything go tight.  He’s also wished many times that Bruce didn’t have to be careful, and there’s a fantasy that’s been percolating in him since the first day he took Bruce’s clothes off in the cage and kissed him and watched him grow and kept on kissing him. He could never tell Bruce about it, it’s so misguided and awful.  It would hurt him.

But he wishes he could keep up.  

He imagines what it would be like if he had a body that could take as much as Bruce’s, if he could feel Bruce growing inside of him and grow along with him, both of them huge and powerful and passionate and _safe_ , and they could fuck each other for all they were worth, like an earthquake. Like gods.

He hates his own limits, hates being so hopelessly breakable when there are so many things he wants to hold close and keep safe forever, and sometimes the way he feels about the man next to him makes that hatred come on so strong that Bruce may as well be as big as the entire world.

“I want to give you everything,” he says.

“I know you do.”  Bruce’s smile is warm for all it’s so sad and Tony hates that too.  “I’m sorry.  It’s ridiculous, me complaining like this when you’ve already given me so much more than I thought I could ever-”

“What if I rode you?” Tony blurts out.

Bruce blinks once, twice.  “Huh?”

“What if I were on top of you?  I’d be able to see you, keep an eye on you.  If you started to so much as tinge green anywhere I could get off easily. We could go slow, probably slower that way than any other, and we could check in as many times as you want or need to. I, personally, would feel completely safe like that.  I wouldn’t be worried at all.  It’s still only one time you even came close to accidentally Hulking out during sex, you realize that?  Just once, and that was – oh god, _ages_ ago.”

“For any sane, rational person,” Bruce points out wryly, “once would have been enough.”

“And if you go by the definition that insanity is doing the same thing and expecting different results, ok, fine.  But those different results have been real, Bruce, and they’re not mine, they’re coming from _you_ , you testing your own waters and staring yourself down.  I believe in those results.  I see them walking and talking every day.”

Bruce puts a hand on Tony’s knee and traces the seam of his pants. “Sometimes I worry what kind of person getting what I want so often is going to turn me into.”

“I’d say you’re turning out pretty stellar so far,” Tony retorts.

When Bruce kisses him it’s like he’s been too long without and forgotten how it feels, like the kinds of kisses he gives after Tony’s been gone for a week on business, fierce and messy.  Tony climbs onto his lap and Bruce tugs at his necktie just right, enough that he can feel it without choking for air.

“How would you feel,” Bruce whispers, “about coming to my bed and getting fucked?”

“Wait, you mean now?  Holy shit you mean _now._ ”

“Before I talk myself back out of it would be ideal, yes.”

Tony makes as if checking Bruce’s pupils for dilation, only half-joking.  “Are you sure you’re entirely sober?”

“Tony, if you’re unwilling to coerce me then you’re at least going to have to let me coerce myself a little.”

“Only if you talk to me.  Habitually.  Frequently.”

“Fair deal.  This is the part,” he breathes right against Tony’s ear, tugging on his tie one last time before moving his fingers over the knot, “where I get you naked.”

They lose their shirts on the sofa and then get distracted by each other’s mouths, so it’s another few minutes before they make their way to the bedroom and lose everything else.

Somehow they know, without having to put it in words, that this isn’t the time for plays of dominance.  Tony doesn’t push or pull Bruce, he simply climbs onto the bed and lays back, and Bruce follows him down.  They kiss side by side, the same reunion-style kisses that manage to be desperate and gentle all at once, until they need to break for air.

“Hey,” Tony says breathlessly, smoothing a lock of hair out of Bruce’s eyes.  “Check-in number one.”  He wants to get fucked, no question, but he thinks that if Bruce wanted to back out and they stayed like this, side by side, kissing and touching and bringing each other off with their hands, he’d fall asleep just as happy.

“I’m good,” Bruce assures him, smoothing his hand over Tony’s shoulders, resting at the small of his back.  “I want to touch you,” he adds, lower and quieter, stroking his fingers down over Tony’s tailbone.  “Like this.  Is that ok?”

“Holy fuck _yes_ it’s ok.”  Tony hooks his outer leg up over Bruce’s waist, giving him plenty of room to work, and is immediately rewarded with Bruce’s finger stroking down and pressing against the pucker of his opening.

There’s nothing in the universe Tony could have done to stop the sound he makes.  Or a single one of the sounds that come after.  Bruce strokes and slides and presses, moving his finger in perfect circles until Tony feels hard all over, blood-flushed and sensitive, his pulse pounding in his ears and his ass, and already his muscles are twitching accidentally-on-purpose, nibbling at Bruce’s fingertip, trying to pull him in deeper.

“Prep me,” he says, and honest to god he meant it to come out as a suggestion and not an order, meant for it to have the lilt of a question, but Bruce groans in a way that implies he’s more than ok with it before digging into the bedside table drawer.

He doesn’t even bother with a glove, just slicks up his finger and makes a few more now-chilly circles around Tony’s entrance before pushing in slow and careful.  It’s only a single finger but Tony’s head clunks back against the headboard and he scratches at the sheets.

“Check-in number two,” he manages to pant, which he thinks takes an admirable amount of effort on his part.

Bruce smiles, drawing back and pushing in again.  “I dreamed about this,” he says calmly, so fucking calmly and Tony’s an absolute mess, whining in the back of his throat.  “So many times.  I’d dream of your body tight around my fingers and my dick and I’d wake up rock-hard and terrified.”  Tony can feel him pressing up around and back, carefully exploring, feels the second ring of muscle relax and accommodate the stretch.  “I could’ve done this a long time ago, I suppose. Worked you with my fingers like this. I’m sorry that I didn’t.”

“It’s ok,” Tony gasps, “no worries, can I have more?  Please? I can definitely take it, I’m ready for it.”

Bruce chuckles and withdraws momentarily, slicking up a second finger.  “I was scared,” he says, sinking in again, and the stretch is a lot and it’s perfect and Tony smacks himself on the headboard _again_ like he’s learned nothing.  Bruce uses his unoccupied hand to soothe the back of his head and Tony moans helpfully to let him know that everything’s great, really excellent, nothing wrong here at all.  “I was afraid of how much I wanted you,” Bruce continues, “almost as much as I was afraid you’d never want this from me, if you took even a few seconds to think about how wrong it could go.”

Since it’s apparently confession time Tony figures he can go big or go home.  “I’ve wanted you inside of me since the first time you kissed me.”

Bruce makes a noise like he’s been physically struck, and his fingers press in and crook, beckoning.  Tony puts his hand on top of Bruce’s and directs him gently.  “Just a little deeper, big guy, all the way to the knuckle, there you go, now curl back and -!”

Pleasure jolts through him, shooting up his spine and through his dick until he feels impossibly hard, and Bruce says “There?” with the slightest hint of teasing in his voice and all Tony can do is nod helplessly before allowing himself to lose his mind completely as Bruce nuzzles his fingertips over and over and over against that perfect place inside of him.

His body starts to scream at him how good it would feel to let himself come like this, to wrap a hand around himself or guide Bruce’s free hand to his cock, and there’s no denying that, he’d fall asleep just as happy that way too, but that’s not what he wants, not what this is for.  “Stop,” he pants, wrapping his fingers around Bruce’s wrist right above where his fingers are buried inside of him.  “Stop stop stop,” and Bruce withdraws, brow furrowing with concern.

“What’s wrong, did I hurt-”

“No, god no, that was amazing, you’re amazing, I just want – I want _you_.” He reaches out and strokes Bruce’s cock for emphasis.  “If you want. If you’re ready.”

Bruce takes a deep, trembling breath. “Ok.”

Tony pushes himself up and guides Bruce with his hands to lie back, then climbs over to straddle his waist, leaning forward to pull a condom out of the drawer.  He opens the package with his teeth, and in the interest of cutting tension he pops the condom into his mouth and goes down.

Bruce laughs softly and tangles his fingers into Tony’s hair.  “You’re such a show-off.”

Tony rolls the last half-inch of latex with his lips and comes back up.  “You’re not complaining.”

“No,” Bruce agrees as Tony slicks up the length of his cock with more lube.  “I’m not.”

Tony rises to his knees, wiping excess lube against his own thighs.  “You ok, big guy?” he asks.  “How are you doing?”

Bruce swallows once, hard enough that Tony can see his throat bob, and raises his hands to Tony’s hips. “Please,” he says softly, rolling his hips, pressing his cock to the curve of Tony’s ass.  “Please.”

Tony reaches behind him with one hand to steady Bruce’s cock, lines himself up, and sinks down, slowly, until he’s seated flush against Bruce’s lap.

It feels better than anything he’s ever tried not to imagine, because it’s _real_.

Stuttering puffs of air fall over Bruce’s lips, like he’s sobbing with his breath instead of his voice.  He moans Tony’s name, just once, and Tony can hear the hint of panic under the pleasure.

“Please don’t be afraid,” he says, as gently as he can, trying his best to sound anything beyond wrecked. “You’re not going to hurt me, Bruce. Neither one of us is going to let that happen.”

Bruce pushes himself up on his hands and Tony leans forward as far as he can without losing the hot, hard presence of Bruce’s cock inside of him, and they kiss, long and wet and deep.

It’s not easy to hang onto thought, with Bruce’s tongue swirling and his cock pulsing, Bruce all around him and in him. He fights like hell not to give up thinking in favor of feeling, to balance them both, but he can’t resist wriggling his hips, clenching his muscles, letting Bruce feel how deep he is.

Bruce feeds him a groan and breaks away, falling back, his hands still on Tony’s hips squeezing hard enough that there might be some light bruising later – but that’s the kind of minor injury Tony’s more than willing to deal with, and he’s made sure time and time again in the past that Bruce knows it, knows where the lines are and exactly how far he can cross.  “You,” he grates, bucking his hips up and making Tony cry out at the sudden intensity of the depth.  “Feel,” and he bucks again, and Tony knows he’s doing it on purpose now, starts to work out a counter-rhythm, pushing up and sinking down.  “ _Incredible_.”

“ _You_ ,” Tony gasps, trying to sync up with their rhythm enough that he can squeeze Bruce with his muscles every time he pulls back, “are one to talk.”

Bruce’s breathless laughter turns into another groan, long and low, as Tony gets the rhythm just right.  He realizes that in his focus he’s allowed his eyes to shut and snaps them back open immediately – Bruce needs his eyes, needs him to see, to keep them safe, but there’s not a trace of green on him. In the lamplight he’s more of a deep burnished gold, with a hint of crimson high in his cheeks, and the light and shadow move over his skin in waves with every roll of his hips.

“You look so good,” he murmurs, rubbing one hand over Bruce’s chest.  “God, Bruce, you’re doing _so good_ ,” and Bruce moans as his own eyes shut, pushing up into Tony with hard, jerky thrusts.  Tony starts crying out on every impact, he can’t _help_ it, he never can when it’s like this, it’s so sensitive and it’s so _much_ , and he lets Bruce take over, fighting to keep his eyes open so that Bruce can keep his shut, wanting more than anything else to let Bruce listen and _feel_.

He has no concept at all of how much time passes before Bruce opens his eyes and says his name again, panicked and desperate, and Tony’s on maximum alert until Bruce lets out a strain of breathy laughter and says, “I can’t, I’m sorry, I _can’t_ , I want to draw it out but there’s just no way-”

Tony raises his hand from Bruce’s chest to his mouth, soaks it with spit and takes his own cock in his hand, jerking himself with brutal force and speed.  “God, yes, _Bruce_ , do it, come on, come inside of me-”

He manages to fall over the edge first, exactly as he’d hoped, and he’s not so overwhelmed by the pleasure of it that he can’t feel Bruce following behind him, brought over by the feeling of Tony convulsing and squeezing all around him.  They pulse and tremble together, hands grabbing each other everywhere they can reach, their voices raised in a perfect chorus of satisfied joy.

“Hey,” Tony says softly, once he’s risen off of Bruce and laid himself out at his side.  “You did it.”

“Hey,” Bruce responds, “I did,” and he pulls Tony into his arms, both of them heedless of the mess on his chest.

“Thank you,” Bruce whispers.  “I didn’t – I wasn’t sure if I could-”  He presses a kiss to Tony’s forehead.  “Thank you.  I love you.  Thank you.”

Someday Bruce will get up, take care of the condom, and wash his hands.  Someday Tony will make it to the shower.  They’ll find some extra sheets or go sleep in a bed that hasn’t been dotted with damp spots of lube and ejaculate.

But for now, they hold each other.


End file.
